1. Field of the Invention
This invention relates to a document sorting system, and more particularly, to a system incorporating a concatenated group of pocket modules for receiving the sorted documents.
2. Description of the Prior Art
A document sorting system sorts documents into discrete groups based on certain identifying indicia or information encoded on the documents. A common document sorter configuration includes a hopper which receives as input a stack of unsorted documents. The documents are fed from the hopper in serial order through a read station where the encoded indicia or information is sensed. The sensed information is transmitted to a control unit that correlates the information with the identification of the group to which each document belongs. Each group is represented as a pocket or bin in a document receiving station. Each pocket branches off a common document transport path. A diverter gate is provided at the mouth of each pocket and may assume an open or closed position depending on whether or not a document is intended to be received in its respective pocket. If the diverter gate is closed, the document is allowed to pass the pocket and continue along the common transport track; if the gate is open, the document will be diverted into the pocket.
The number of pockets or bins required varies from one application to the next depending upon the number of discrete groups. A convenient solution for providing the required number of pockets is to concatenate a plurality of pocket modules where each module contains a uniform plurality of pockets. When additional pockets are needed, one or more modules are added to the concatenation; and when fewer pockets are needed, modules are simply removed. Modules with four pockets each are common in the industry.
When a module is placed in or added to a concatenation, each pocket of the module must have a unique identification in the concatenation so that it can be accessed by the control unit. As may be readily deduced, the identification of a pocket is dependent upon the relative position of its associated module in the concatenation. The fact that module position must be taken into account in assigning pocket identification is a basic limitation on the otherwise free interchangeability of modularity of pocket modules.
In the prior art, a common way of assigning a unique identification code to each pocket of the module was to set a group of mechanical switches in the module to create a binary identification code for each pocket. The switches were generally contained within the module and manually set and reset each time the module would assume a different relative position in the concatenation.
The setting and resetting of switches provides a workable means for the assignment of a unique identifying code for each pocket in the concatenation. However, in practice it generally requires that the back panel of the module be removed, the operator reset the switches, and then replace the back panel before the module becomes operative. This technique is clostly in terms of time and operator effort. It also introduces the possibility of error due to human intervention.
Against this background, it would be clear improvement over the prior art to provide a pocket module that independently generates a unique identifying code for each pocket of the module and eliminates costly and error-prone manual operations. Such a module would be fully interchangeable and plug-compatible without regard to its previous position in a concatenation and provide truely modular capability.